The prior art discloses various types of firearm action assemblies for attenuating, or reducing the recoil associated with a firearm cartridge discharge. A first example of these is depicted in Benelli U.S. Pat. No. 3,893,369 which teaches a pistol having a bolt provided with ribs extending transversely to the bolt axis and adapted to engage in and disengage from corresponding mating grooves provided in the receiver breech upon a slight rotation of said bolt with respect to said receiver breech. A locking link provided between the bolt and the bolt carrier is caused, upon firing, to rotate in such a direction that said link holds said bolt urged against the receiver breech, with said ribs engaged in the mating grooves. Once the inertial force of said bolt carrier has failed, the residual pressure of exhaust gases applies a force to said bolt which causes the bolt to rotate with respect to said receiver breech so as to disengage said ribs from the associated grooves in said receiver breech.
A further example is depicted in Plumb, US 2016/0370135 which teaches a recoil impulse reducing bolt carrier group including a main bolt carrier group body for the intended weapon system and a recoil impulse reducing assembly. The recoil impulse reducing assembly fits inside the main bolt carrier group body. The recoil impulse reducing assembly includes an interchangeable weight and a dampener, such as springs or fluid. The weight moves within the main bolt carrier group body under hydraulic and/or spring tension. The recoil impulse reducing bolt carrier group manipulates weight distribution during the operation of the firearm to prevent and reduce front and rear recoil forces from affecting the firearm.
Another example is shown in Kerbrat U.S. Pat. No. 8,783,158 for a delayed blowback mechanism including a main frame (1) and its extension (1′), which accommodate a barrel (21) with fixed mounting, a mobile bolt (22) and its guiding pin ensemble (66) and main spring (67) moving in the main frame (1), a mobile mass (34) and its assembly of guiding pin (60), push plate (61) and return spring (62), and a mobile mass catch sear (42) and its spring (7). The mobile mass pivots from a first position under the barrel to a downward position in reaction to the backward movement of the mobile bolt. The placement of the mobile mass in front of the chamber directs counteracting forces down on the barrel to prevent muzzle climb during operation.
Finally, another example of a recoil absorption device, such as for use within the family of semi-automatic or automatic AR-15/M-16 and M4 carbines, is depicted in U.S. Pat. No. 9,103,611 to Neitzling which teaches a barrel attached to and upper receiver and including a compressible bolt carrier extension system. The compressible bolt carrier extension system includes a bolt carrier, an extension spring, two pins, and a reciprocation bolt carrier extension piece. As a whole, the compressible bolt carrier extension system makes possible the use of elongated upper and lower receivers to be used for chambering long-action or other center fire cartridges for use with AR rifles such as the M-16, and M4 etc., eliminating the need for any buffer or buffer tubes other than those commercially available. A further advantage of the compressible bolt carrier extension system is the reduction of felt recoil as the system fully loads during the recoil stroke as it pushes against the buffer absorbing additional recoil energy. The system can be incorporated into firearms using a variety of cartridges.